deficiency

[Dominick]

what might be the cause of this

 

[fish_4_all]

Looks like what my vals did when I took out my CO2.

 

[rich311k]

What size tank? How much light? Are you dosing anything? Can you give us you test results. Nitrate, PH, KH, phosphate? I would guess a potassium deficiency at first guess.

 

[Dominick]

and your guess is probably right considering i wasent able to dose anything in like a month

 

[zenkatydid]

i was led to believe that a potasssium deficiency displayed as yellow/brown spots on the leaves. i am no expert but that looks to me more like a calcium deficiency.

 

[rkilling1]

i was led to believe that a potasssium deficiency displayed as yellow/brown spots on the leaves. i am no expert but that looks to me more like a calcium deficiency.

Yes (to an extent, but lack of K will also cause withering of leaf edges and tips), but the problem is, once you start adding more element deficiencies together, it is hard to tell exactly what is causing it. A plant with a K or CA deficiency will look quite different then one with a K and Ca deficiency. (this could be one of those cases)

If it is a Ca alone, it will be effecting both the newer and older leaves. If it is a K deficiency, that only effects the older leaves due to elemental mobility of that element within the plant. ie the older leaves will transfer the needed elements to the newer leaves.

reference:

http://www.aquatic-gardeners.org/elemental.html

and

http://www.thekrib.com/Plants/Fertilizer/nutrient-deficiency.html